1. Field of the Invention
This invention is directed to a flush or recess mounted light fixture assembly comprising an illumination assembly incorporating a light emitting diode (LED) array and a heat sink which is configured and disposed to efficiently dissipate heat by radiation rather than merely by conductivity, so as to maximize the appearance and illumination qualities of the light fixture and substantially diminish power limitations that result from limitations in heat dissipation.
2. Description of the Related Art
Various types of illumination assemblies which incorporate light emitting diodes (LED) as the light generating component have become increasingly popular in recent years. Such an increase in popularity is due, at least in part, to their overall efficiency as well as the ability to define various lighting arrays readily adaptable to numerous practical installations or applications.
Accordingly, LEDs are known for use in high power applications such as spotlights, automotive headlights, etc. However, due to their recognized versatility LEDs are also utilized extensively in various types of luminaires and/or like fixtures installed in conventional domestic and commercial environments. Such applications allow for the illumination of a given area in an efficient and variably decorative manner in that associated light fixtures may take the form of standard or customized lighting arrays, wall or ceiling mounted fixtures, inset lighting, etc. Further, LEDs provide increased energy efficiency and effective illumination output from the various types of light fixtures installed, while reducing maintenance costs associated therewith.
Therefore, the use of illumination assemblies incorporating collective LED arrays offer significant advantages in terms of increased lighting and efficiency of operation. However, certain disadvantages and problems associated with the use of LED based illumination assemblies are commonly recognized. More specifically, a primary concern with the structuring and use of LED illumination assemblies is the management or dissipation of excessive heat generated by the LED array. More specifically, the light intensity generated by an LED light source is generally a proportional function of its operational temperature. As such, LED illumination assemblies tend to generate a significant amount of heat during their operation, which in turn may derogatorily affect the light generated by the LED array as well as reduce the reliability and operational life thereof. Accordingly, the operable life of many LED based illumination assemblies may be significantly reduced due to premature failure of one or more light emitting diodes associated with a light fixture or other device, and/or the maximization of power and illuminating output for such an illumination assembly is limited.
Therefore, it is commonly recognized in the lighting industry that heat management and more specifically, heat dissipation is a critical structural and operational consideration in the manufacture, use, installation and overall viability of illumination assemblies incorporating light emitting diodes as the primary or exclusive light generating structure. Known attempts to overcome the problems associated with the generation of excessive heat involve the creation of diverse heat dissipating structures. By way of example, printed circuit boards have been disposed in a multi-layered or stacked array in attempt to transfer heat away from the LED array. Alternatively, one or more printed circuit boards associated with the operational control of the LED light generating structures include a metal core disposed and structured to further effect heat dissipation.
Other known or conventionally proposed solutions to the heat management problem include the utilization of a heat absorber including a heat conductive resin disposed in communicating relation with the circuitry of the LED array. Also, heat absorbing structures may be utilized which have a large physical configuration such as, but not limited to, a multi-finned structure providing a conductive path of heat transfer towards an area of dissipation. However, many known attempts do not effectively accomplish optimal heat transfer, resulting in lower operational performance and a reduced operational life as generally set forth above.
Accordingly, there is a long recognized need in the lighting industry for an efficient and practical heat dissipation assembly preferably of the type which may be easily included in the structure of a light fixture. Moreover, there is especially a need as it relates to recessed or flush lighting wherein traditional heat dissipating structures are hampered by being contained within a wall or other mounting surface. Specifically, known recessed or flush mounting structure typically include large unattractive heat sinks contained within the mounting surface and/or otherwise concealed. Because of their concealed positioning, these heat sinks rely on heat conduction to draw heat away from the light source, and thus are constructed so as to maximize their surface area within a contained location through the use of large numbers of vanes and ridges. Even then, however, there are limitations on the power and illumination ability of the light source, as there are usually space and weight constraints for the recessed heat sink, especially in the context of a retrofit wherein the cavity into which the light source will be positioned has been pre-defined based upon conventional incandescent lighting specifications.
Thus, it would be beneficial to provide an improved illumination assembly that would allow the light fixture to assume any number of design configurations best suited to the aesthetic and illumination requirements of a specific application without being hampered or limited by the heat dissipation requirements. It would also be beneficial to provide an illuminations assembly that has significant heat dissipating capabilities and is not limited by space constraints within a mounting surface so as to be capable of an optimal level of light generation, while at the same time enjoying an extended operational life. Also, such an improved proposed light fixture should also include structural components which serve to effectively isolate or segregate the conductive material components associated with heat dissipation from direct contact with any type of electrical conductor.
Therefore, the proposed light fixture assembly would accomplish effective heat dissipation from an LED based illumination assembly, while at the same time assuring operational safety. Further, the proposed light fixture would be capable of sufficient structural and operational versatility to permit the light fixture to assume any of a variety of utilitarian and aesthetic configurations and would not need to sacrifice light emitting capabilities due to overheating.